DE3915121A1 - NEW N-ALKYL GLYCAMINE COMPOUNDS AND A METHOD OF PREPARING THEM AND USE THEREOF - Google Patents

Description

The invention relates to novel N-alkylglykaminoverbindungen, as well as a Process for the preparation and its use.

Renewable resources are important raw materials for the detergent industry. and body care area. In addition to the vegetable oils and animal Fats are increasingly gaining strength and monosaccharides. The first polyglycosides and saccharide esters are already considered environmentally friendly Surfactants offered in the market. Monosaccharide-based glycamines also provide good starting materials for washing active and body care applications. B. tertiary and quaternary fatty alkylglycammonium salts as cationic detergents mentioned (US-PSS 20 60 850, 20 60 851). Corresponding ethoxylated Compounds are called low-foaming rinsing and cleaning agents and as a skin and hair care product proposed (FR-PS 15 73 085, DE-OS 22 00 040, JP 5 92 12 421). Also known are nonionic detergents based on fatty acid N-alkylglycamides, which are particularly kind to the skin and at the same time have a thickening effect on shampoo and shower formulations (US-PS 27 03 798, DE-OS 37 11 776).

Amphoteric surfactants represent a class of substances, depending on the environment setting (acidic, neutral or alkaline) itself as anionic or cationic surfactants, d. H. they have electronegative and electropositive building blocks in the same molecule combined. You win increasingly important in the personal care sector, as they are a special have good skin tolerance and low toxicity and show in mildly acidic medium as a mild surfactant good effect.

In general, these are N-substituted amino acids of the following type (formula I):  

in the R₁ for a longer fatty alkyl chain and R₂ z. For a shorter one Alkyl radical stand. R₃ can be both a proton or an alkyl radical represent. In their behavior becomes clear between the amino acids with tetrasubstituted nitrogen and those with trisubstituted Nitrogen differentiated:

The tetrasubstituted amino acids are also betaines (formula II) called. They have a fixed one regardless of the pH of the environment positive charge. In the neutral and alkali region, the isoelectric, obtained zwitterionic character; behaves in the acidic range Betaine acts like a cationic surfactant.

The trisubstituted amino acids (formula III), however, represent real Ampholytes

In the neutral region, they form internal salts; in the acidic medium they go in cations, in the alkaline range in anions.

A disadvantage of the known N-trisubstituted amphoteric surfactants is that they are in the desired pH range, namely slightly acidic to neutral, when used in the personal care sector, such as hair and shower shampoos, a minimum in solubility, foaming power and wetting power [Surfactants Detergents 23 (1986) 309].

The invention is therefore based on the object, improved N-trisubstituted Amphoteric surfactants based on monosaccharides find as renewable raw materials, which also the aforementioned disadvantages do not have.

This object has been achieved by the glycaminoacetic acid / acetate solved the formula IV.  

The subject of the invention are therefore N-alkylglycamino compounds the general formula IV

in the n 4-24, and

X is Na, K or H

N-alkyl-N- (deoxyhexityl) -acetic acid salts are the general ones Formula IV

in which n is 4-24, preferably 8-14, and R is preferably a deoxyhexityl radical, such as. 1-deoxy-1-glucityl, 2-deoxy-2-glucityl, 3-deoxy-3-glucityl, 1-deoxy-1-mannityl, 2-deoxy-2-mannityl, 3-deoxy 3-mannityl, 1-deoxy-1-dulcityl, 2-deoxy-2-dulcityl, 3-deoxy-3-dulcityl, 1-deoxy-1-allityl, 2-deoxy-2-allityl -, 3-deoxy-3-allityl, 1-deoxy-1-altrityl, 2-deoxy-2-altrityl, 3-deoxy-3-altrityl, 1-deoxy-1-talityl, 2-deoxy -2-tality or 3-deoxy-3-talityl; preferably R is a 1-deoxy-1-glucityl radical, and X is preferably Na.

It has now surprisingly been found that these trisubstituted, amphoteric compounds of formula IV excellent have surfactant properties. They are tris-substituted, amphoteric surfactants of formula III readily soluble in water. In addition, the trisubstituted amphoteric surfactants of the invention a good skin compatibility. It shows in particular the C₁₂-alkylglucaminoacetate outstanding properties: in the entire pH range From 2 to 12 no opalescence occurs, but it is clear soluble.

The preparation of chemical compounds of the formula IV takes place by carboxymethylation of N-alkylglycamines, such as. N-alkyl-1-amino-1-deoxyhexitylene, according to well-known method depending on Solubility of the amine in water or butanol as solvent. In compliance the pH range of 8-9 by continuous addition of Alkali and maintaining a reaction temperature of less than 80 ° C. Thus, a selective N-carboxymethylation is achieved without the OH groups of the hexityl radical react.

The N-alkylglycamines themselves are prepared by well-known methods the reductive amination of monosaccharides (US-PSS 19 94 467, 20 16 962), in particular hexoses with alkylamines such. Butylamine, Octylamine, laurylamine, myristylamine, stearylamine or coconut fatty amine prepared as examples of the monosaccharides are: Glucose, galactose, mannose, fructose, allose, altrose, talose as well Glucose syrup.

The invention will be illustrated by the following examples.  

Preparation Examples 1. octylglucaminoacetic acid Na salt

19.4 g (0.205 mol) of chloroacetic acid are dissolved in 106.2 g (5.9 mol) of water dissolved and 58.6 g (0.2 mol) of octylglucamine in portions with stirring added. At the same time the temperature is raised to 60 ° C. To complete dissolution of octylglucamine, 102.4 g (88 ml, 0.409 mol) of a 16% sodium hydroxide solution at a pH between 8 and 9 added dropwise. Towards the end of the reaction the temperature rises to 65 ° C elevated. After completion of the sodium hydroxide addition is allowed for 1 h at 70 ° C. afterreact. In the cold, the unreacted octylglucamine falls (6.5 g, m.p .: 121-123 ° C, base number: 183.6 mg KOH / g) and becomes filtered off. The filtrate is then concentrated to dryness.

Yield: 78.6 g (83.2%) Melting range: 80-154 ° C Nitrogen content: 3.01% (3.75%) Carboxyl number: 121 mg KOH / g Purity: 79% octylglucaminoacetic acid Na (13 C-NMR) 6% Na glycolate 15% NaCl

2. Decylglucaminoacetic acid Na salt

19.4 g (0.205 mol) of chloroacetic acid are dissolved in 192.6 g (2.6 mol) of n-butanol dissolved and 64.2 g (0.2 mol) of decylglucamine in portions below Stirring added. The temperature is raised to 60 ° C. To complete dissolution of the decylglucamine, 102.4 g (88 ml, 0.409 mol) of a 15% sodium hydroxide solution at a pH between 8 and 9 added dropwise. Towards the end of the reaction the temperature rises to 65 ° C elevated. After completion of the sodium hydroxide addition is allowed for 1 h at 70 ° C. afterreact. Subsequently, the water is under continuous distilled off n-butanol addition azeotropically. This occurs a precipitation of NaCl on. This is filtered off hot. For this filtrate occurs in the cold a white precipitate.

The separated precipitate becomes hot in water at a ratio of 1: 3 dissolved and then cooled. In this case, the unreacted decylglucamine falls (2.5 g, mp.: 122-123 ° C, base number: 170 mg KOH / g)  and is filtered off. The filtrate is concentrated to dryness.

Yield: 67.4 g (84% theory) Melting range: 95-171 ° C Nitrogen content: 3.25% Carboxyl number: 132.0 mg KOH / g Purity: 92.7% decylglucaminoacetic acid Na (13 C-NMR) 2.6% decylglucamine 4.2% Na glycolate 0.51% NaCl

3. Dodecylglucaminoacetic acid Na salt

As in Example 2, chloroacetic acid is reacted with dodecylglucamine.

Yield: 71.5 g (83.3% theory) Melting point: 172-174 ° C Nitrogen content: 3.07% Carboxy-number: 115.3 mg KOH / g Purity: 96.0% dodecylglucaminoacetic acid Na (13 C-NMR) 2.4% Na glycolate 1.6% NaCl

4. Tetradecylglucaminoacetic acid Na salt

As in Example 2, chloroacetic acid is reacted with tetradecylglucamine.

Yield: 94.9 g (97.8% theory) Melting range: 160-162 ° C Nitrogen content: 2.88% Carboxy-number: 111.6 mg KOH / g Purity: 97.8% tetradecylglucaminoacetic acid Na (13 C-NMR) 1.8% Na glycolate 0.4% NaCl

5. Octadecylglucaminoacetic acid Na salt

As in Example 2, chloroacetic acid is reacted with octadecylglucamine.

Yield: 91.8 g (89.5% theory) Melting range: 75-210 ° C dec. Nitrogen content: 3.72% Purity: 83.6% octadecylglucaminoacetic acid Na (13 C-NMR) 12.8% octadecylglucamine 3.3% Na glycolate 0.30% NaCl

Examples of properties for use as a surfactant 6. Surface / Surface Tension and Crit. Micelle Formation Concentration

The alkylglucaminoacetates synthesized according to the preparation examples were measured with n = 8, 10, 12, 14, 16 and 18 as 1% strength aqueous solutions after adjustment to pH 5.6.

Fig. 1 shows the results of the measurement of the interfacial tension and the surface tension (lower part of the figure) as well as the critical micelle concentration using the Landa tensiometer (upper part of the figure) measured against air or paraffin according to the Noüy ring method.

In their surfactant properties, the glucaminoacetates in relating to the lowering of the surface and interfacial tension classic behavior.

For comparison, the surface and interfacial tension and the critical micelle concentration of Carboxymethyldimethylcocosfettammoniumbetains (RN⁺ (CH₃) ₂-CH₂COO ^- with R = C₁₂-C₁₄), a marketable betaine, determined (see Table 1).

Table 1

Boundary / surface tension and critical micelle concentration (c _k value)

7. Foaming power

The alkylglucaminoacetates used in Example 6 were used as 0.1% aqueous solution at the pH settings 9.9 ± 0.3; 7.00 and 5.60 measured according to DIN 53 902. At pH 7.00 and 5.60, the C₁₆- and C₁₈-glucaminoacetic acids insufficient solubility. The results are shown in Figures 2a (for pH 9.9 ± 0.3), 2b (for pH 7.00) and 2c (for pH 5.60). The solid curve means the values after 30 seconds and the dashed curve the values after 300 seconds.

The maximum foaming power was achieved with the dodecylglucaminoacetate. The values achieved (reading after 30 s / 300 s) of 580 ml / 560 ml are comparable to those of the commercial anionic surfactant (MARLON® A: alkylbenzenesulfonate) of 590 ml / 570 ml and are significantly higher than those of ether sulfate (MARLINAT® 242 : C _12-14 with 2,2-EO) at 540 ml / 540 ml and the carboxymethyl dimethyl coconut fatty ammonium betaine at 510 ml / 500 ml.

A pH dependence can be despite the ampholytic character do not observe the alkylglucamino compounds.

By blending the alkylglucamino compounds with the surfactant MARLINAT® 242, the foaming power of the short-chain alkylglucaminoacetic acids is significantly increased. The maximum is also reached with the dodecylglucaminoacetate (see Fig. 3: measured at pH 5.60, values after 30 seconds, values after 300 seconds).

8. Wetting on the hair

The use of a surfactant in shampoos requires a good wetting of the Hair ahead. To assess the wetting was the contact angle between a partially dipped hair and the surface of the Tenside solution used [Colloids and Surfaces 6 (1983) 49-61].

The dodecylglucaminoacetic acid Na salt shows as 0.1% surfactant solution at pH 6, based on water, a Randwinkelerniedrigung of 53.8%.

9. Skin compatibility

The skin compatibility was determined by the zein test according to Götte (CID Brussels 1984, 83-90). Fig. 4 shows the results for the Alkylglucaminoessigsäure Na salts of Examples 1 to 4 in 1% aqueous solution at pH 5.6.

The determined zein numbers indicate a very good skin compatibility shut down. They are well below the value of the commercial one Anionic surfactants MARLON® A of 510 mg N / 100 ml and are comparable with those of betaines that use zein numbers by 50 mg N / 100 ml be achieved.

Claims (9)

1. N-alkylglycamino compounds of the general formula IV in the n 4-24, and X is Na, K or H 2. N-Alkylglykaminoverbindungen the general formula IV according to claim 1, characterized in that n is 8-14. 3. N-Alkylglykaminoverbindungen the general formula IV according to claim 1, characterized in that means. 4. N-Alkylglykaminoverbindungen the general formula IV according to claim 1, characterized, that X means Na. 5. Process for the preparation of N-alkylglycamino compounds according to to claims 1 to 4, characterized, that the corresponding N-alkylglycamines at pH 8 to 9 and T <80 ° C. in a conventional manner N-carboxymethylated by means of chloroacetic acid are made by adding alkali hydroxide. 6. A process for the preparation of N-alkylglycamino compounds according to Claim 5, characterized, that is used as the alkali metal hydroxide sodium hydroxide. 7. Use of N-Alkylglykaminoverbindungen according to claim 1 as Surfactant. 8. Use of N-Alkylglykaminoverbindungen according to claim 7 as Amphoteric surfactant. 9. Use of N-alkylglycamino compounds according to claim 7 in Personal protection products.